Microwave sintering of dense and lattice 3Y-TZP samples shaped by digital light processing

Nowadays it is possible to produce ceramic parts with solid and complex shapes with rapid and efficient shaping and sintering techniques. In this paper, 3mol% yttria stabilized zirconia (3Y-TZP) dense and lattice parts were shaped by Digital light processing method (DLP) and densified by conventional (CV) and microwave (MW) sintering. 3Y-TZP samples were MW sintered up to 1550 °C with different heating rates (10, 30, and 50 °C/min) for the dense samples and 30 °C/min for the lattice samples. Controlled thermal cycles with a homogenous heating and no thermal runaway was reached. CV sintering was carried out at 10 °C/min up to 1550 °C. No inter-layer delamination was detected after sintering by the two methods. Both dense and lattice MW-sintered samples reached high final densities (equivalent to obtained values with CV-sintered samples, i.e., ≥98% T.D.), but exhibited a lower average grain size than CV-sintered materials. The different architectures between dense and lattice samples resulted in a different specific absorbed power: the power absorbed by the dense sample is lower than that absorbed by the lattice one meaning that this sample architecture heats up easily

On radial Schrödinger operators with a Coulomb potential

International audienceThis paper presents a thorough analysis of 1-dimensional Schrödinger operators whose potential is a linear combination of the Coulomb term 1/r and the centrifugal term 1/r 2. We allow both coupling constants to be complex. Using natural boundary conditions at 0, a two parameter holomorphic family of closed operators on L 2 (R +) is introduced. We call them the Whittaker operators, since in the mathematical literature their eigenvalue equation is called the Whittaker equation. Spectral and scattering theory for Whittaker operators is studied. Whittaker operators appear in quantum mechanics as the radial part of the Schrödinger operator with a Coulomb potential

Proceedings of First Conference for Engineering Sciences and Technology: Vol. 2

This volume contains contributed articles of Track 4, Track 5 & Track 6, presented in the conference CEST-2018, organized by Faculty of Engineering Garaboulli, and Faculty of Engineering, Al-khoms, Elmergib University (Libya) on 25-27 September 2018. Track 4: Industrial, Structural Technologies and Science Material Track 5: Engineering Systems and Sustainable Development Track 6: Engineering Management Other articles of Track 1, 2 & 3 have been published in volume 1 of the proceedings at this lin